Tracti-on, Tracti-off

I own an all-wheel-drive 2006 Lexus IS. It will not climb my steep driveway after a snowfall. Instead, the traction control shuts the motor down to idle, and there's no button to turn off the system. My 2009 IS has the switch, allowing it to make it up the drive with no problem. Is there any way to defeat the 2006's traction control?

There's irony in a traction-control system actually making it harder to climb a slippery hill. This nanny is designed to prevent your car from fishtailing or spinning its wheels under acceleration by cutting power or applying the brakes at the drive wheels, but that's the opposite of what's needed in certain situations. When the road is simply slippery—light mud, a dusting of snow, rain—it usually works well. In some cases, however, the tire and road-surface combination requires wheelspin for forward progress. Some traction-control systems, especially older ones, are too dumb to know.

More From Road & Track

Most new cars have a button or menu option to turn off traction control. For those that don't, like your 2006 IS, there are often built-in workarounds meant for service or emissions testing on a dynamometer. A little Googling turned up a method for disabling traction control on early Lexuses. It sounds tricky, but it works:

1. Start the engine with the parking brake engaged and the brake pedal depressed.

2. Pump the brake pedal twice.

3. While holding the brake down, release and engage the parking brake twice.

4. Pump the brake pedal two more times.

5. The traction-control light should come on, telling you the system is deactivated.

This is an involved process, and you may not want to go through it every time you pull into your driveway. Other options: Pull the fuse for the traction control (note that it will likely also disable ABS and stability control), or park the 2006 at the bottom of the hill and use the 2009 as a shuttle to the house. And if you haven't already, try some winter tires.

Timing Is Everything

My 2005 Infiniti G35 has a noninterference engine with timing chains—a primary and two secondaries—not belts. The manual doesn't mention any required maintenance. Does this mean they never need replacement? My experience with motorcycle chains shows they are prone to stretch and the occasional failure, likely due to exposure to the elements. Are automotive chains different?

As with many differences when it comes to automobiles, the choice between a timing chain and a timing belt comes down to cost. Timing belts are cheaper to manufacture and assemble. Belts can also be serviced more easily, and because the mechanic doesn't have to disturb the oil-tight covers and gaskets that a chain requires, replacement cost is usually lower. Most manufacturers recommend a timing-belt change between 60,000 and 100,000 miles.

As far as failure, timing belts are more predictable in terms of mileage, but they give no warning prior to breakage. On a noninterference engine, a broken belt will stop the valvetrain, stopping the engine; replacement will solve the problem. In most other cases—generally referred to as interference engines, and your car's falls into that category—stopped, open valves will hit moving pistons, something that usually prompts expensive repair.

A timing chain will often sound a cry for help—a metallic rattle—prior to breakage. This early warning often heads off the valve-bending event because most chains will take a lot of abuse before coming apart. If you start to hear funny noises from the engine bay, have the car looked at. Until then, regular oil changes are the only maintenance requirement.

Unlike motorcycle chains, automotive timing chains and their tensioners are shielded from the environment and constantly lubricated. Chains are superior to belts in most ways. They're made of metal, so they typically last much longer than rubber belts, but either component can fail. Nothing lasts forever.